<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport"
        content="width=device-width, user-scalable=no,initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0">
    <title>Document</title>
    <style type="text/css">
        .box{
            width: 300px;
            height: 300px;               
            background-color: gold;
        }

    </style>
</head>
<body>
    <div class="box">DIV 里面的文字</div>

</body>
</html>